Defined Benefit Retirement Plan (Narrative) (Details) - JVB Plan [Member] - USD ($)	3 Months Ended	12 Months Ended
Mar. 31, 2020	Dec. 31, 2007
Defined Benefit Plan Disclosure [Line Items]
Percentage of vested benefit		100.00%
Excess funds transferred to 401(k) plan	$ 431,000

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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